The present invention relates to the mounting of a drive motor in the fuser section of an electrophotographic copier/printer apparatus and in one of its aspects relates to an assembly for mounting a drive motor in the fuser section of an electrophotographic apparatus which allows the motor to be removed and replaced from outside the fuser section housing.
In a typical electrophotographic machine (e.g. copier, duplicators, printers, etc.), a continuous loop of photoconductor film is commonly used to transfer an image from an input section onto a receiving medium (e.g. a sheet of paper). The film is initially charged and then passes through an input section where an image (i.e. analog or digital) is projected onto the charged film. The film then moves through a developing section where a toner is applied to the charged image, and on through an image transfer section where the image is transferred to the sheet of paper or other medium. The paper is subsequently passed through a fuser section where the toner forming the image is fixed to the paper by elevated temperature and pressure. This is typically accomplished by passing the paper between two, opposed rollers, i.e. a pressure roller and a fuser roller, one of which is heated.
In fuser sections such as described above, it is usual practice to drive only one of the rollers. That is, in several known electrophotographic machines, a drive motor is used to drive the pressure roller which, in turn, drives the fuser roller by frictional contact therewith. As will be fully understood by those skilled in this art, this drive motor may xe2x80x9cwear-outxe2x80x9d or experience some malfunction from time to time during the operational life of the machine. When this occurs, the motor must be removed and replaced in order to get the machine back up and running.
In known prior art electrophotographic machines of this type, the drive motor for the pressure roller is secured in position on the outside of the housing of fuser section by means of a plurality of bolts or screws which, in turn, have to be installed from inside the fuser housing. These screws extend from the inside of the housing, through openings in said housing, and into mounting holes which are provided in the face of the motor by the manufacturer of the motor. As will be understood in this art, the inside of the fuser housing is severely crowded with rollers and a multitude of other components, making it necessary to remove some of these components in order to access the mounting bolts for the motor.
As will be appreciated by those who depend on such machines in their commercial operations, time is normally of the essence. Therefore, it is imperative that downtime of the machine be kept to a minimum and that all maintenance/service operations be performed in as short of time as possible. Further, to keep maintenance/service costs down, the more frequently required maintenance operations should be capable of being carried out by a single service person with a minimum of special tools, if any. In some cases, if the maintenance/service operations are simple enough, the owner or user of the machine may train an employee to carry out such operations without requiring the services of an contractor.
Accordingly, it is desirable to eliminate the requirement that components be removed and replaced within the fuser housing each time it becomes necessary to remove and/or replace the drive motor for the pressure roller. By doing so, the motor can quickly be removed and replaced by a single technician thereby keeping downtime for the machine to a minimum.
The present invention provides an electrophotographic apparatus including a means for mounting a drive motor on the outside of the housing of a fuser section whereby the drive motor can be removed and replaced from the outside of the housing without accessing the inside of the housing. This eliminates the need for a technician to remove and then replace any of the components within the fuser section housing during the removal and replacement of the drive motor.
More specifically, the means for mounting the drive motor on the fuser section housing is comprised of a mounting structure affixed to one of the walls of the housing and an adapter plate which is affixed to the face of a standard, commercially-available drive motor. The mounting structure is comprised of a stub extension and a plurality of mounting holes spaced outward therefrom. The stub extension has a central bore for receiving (a) the gear on the drive motor which meshes with the gear on the pressure roller in the fuser housing and (b) a portion of hub of the drive motor. The central bore is stepped to provide a shoulder which supports the hub of the drive motor when the motor is in an operable position within the central bore thereby properly positioning the gear on the drive motor in relation to the gear on the pressure roller. Preferably, the mounting structure is cast as an integral part of the housing wall.
The adapter plate has a main opening therein through which the hub of the motor extends and to a short distance beyond. It is this short portion of the hub that is received into the central bore of the mounting structure when the adapter plate is positioned on the mounting structure. A plurality of openings surround the main opening and positioned to align with the threaded holes in the face of the drive motor which are provided therein by the motor""s manufacturer. The adapter plate is secured to the face of the drive motor by means of threaded members (e.g. screws) through the aligned openings and holes.
The adapter plate has a plurality of mounting openings near its outer periphery which align with the threaded holes in the mounting structure. Threaded members (e.g. bolts) pass through the mounting openings and into the threaded holes to secure the drive motor onto the housing of the fuser section. It can be seen that by securing the drive motor to the fuser housing with bolts that are readily accessible from outside the housing, removal and replacement of the drive motor is significantly simplified resulting in shorter downtimes and less effort required of the technician.